1. [-l1 Points] ZILLDIFFEQQ 3.1.004. PRACTICE ANOTHER The population of bacteria in a Culture grows at a rate proportional to the number of bacteria present at time t. After 3 hours it is observed that 500 bacteria are present. After 10 hours 4000 bacteria are present. What was the initial number of bacteria' (Round your answer to the nearest integer) bacteria Need Help? Submit Answer 2. [/1 Points] ZILLDIFFEQB 3.1.007. PRACTICE ANOTH ER Initially 100 milligrams of a radioactive substance was present. After 6 hours the mass had decreased by 5%. If the rate of decay Is proportional to the amount of the substance present at tlme t, determine the halfrllfe of the radioactive substance. (Round your answer to one decimal place.) :hr Need Help? 3. [l1 Points] DETAILS ZILLDIFFEQB 3.1.009. MY NOTES PRACTICE ANOTHER When a vertical beam of light passes through a transparent medium, the rate at which its intensity I decreases is proportional to Rt), Where t represents the thickness of the medium (in feet). In Clear seawater, the intensity 3 feet below the Surface is 25% of the initial Intensity ID of the Incident beam. What is the intensity of the beam 13 feet below the surface? (Give your answer in terms of IO. Round any constants or coefficients to five decimal places.) Need Help? @ 4. [-/1 Points] DETAILS ZILLDIFFEQ9 3.1.023. MY NOTES PRACTICE ANOTHER A large tank is filled to capacity with 600 gallons of pure water. Brine containing 5 pounds of salt per gallon is pumped into the tank at a rate of 6 gal/min. The well-mixed solution is pumped out at the same rate. Find the number A(t) of pounds of salt in the tank at time t. A(t) = Need Help? Read It Watch It 5. [-/2 Points] DETAILS ZILLDIFFEQ9 3.1.031. MY NOTES PRACTICE ANOTHER A 100-volt electromotive force is applied to an RC-series circuit in which the resistance is 400 ohms and the capacitance is 10-* farad. Find the charge q(t) on the capacitor if q(0) = 0. q(t) = Find the current i(t). i(t ) = Need Help? Read Itb. [-73 Points] DETAILS ZILLDIFFEQy 3. 1.034. An LR-series circuit has a variable inductor with the inductance defined by L ( t ) = _t, 20 Ost